In a fresh batch of TV ads and on recent campaign stops in Grove City in the west and Hazelton in the east, Santorum has sought to highlight how he and Democrat Bob Casey disagree over how to deal with all the illegal immigrants in this country.

Santorum has opposed a measure backed by President Bush that could allow a majority of illegal immigrants already here to eventually become legal permanent residents, by paying fines, fees and back taxes and learning English. Casey said he would support it.

Politics of immigration
Santorum has attacked the plan as amnesty for illegal immigrants. Casey has said it does not constitute amnesty.

Santorum's message has the potential to rally conservative voters, particularly those in the southwest worried about the loss of manufacturing jobs and in the east in towns that have seen an increase in recent years in the number of foreign-born residents.

But he also risks alienating some voters sympathetic to the plight of illegal immigrants. Others concerned about the Iraq war and economy might not see the issue as relevant.

Santorum, who has trailed his opponent for months in polls, said he's talking about immigration because, he said, it is one of the issues uppermost on voters' minds as he travels the state. He's promoting a plan that, in part, encourages the creation of an employer verification program and a temporary worker program where someone already illegally in the United States would have to leave the country first before getting permission to participate.
2006 key races

"We feel very strong that we have a message that is not anti-immigrant or anti-Hispanic, it is pro-security," Santorum, the No. 3 Senate Republican, said in an interview last week. "It is pro the integrity of our country and our borders to make sure that people who come into this country come here for the right reason and the right purpose and that is to become integrated into society."

Democratic response
Casey said Santorum does not have a voting record that backs up his message. The Democrat also said his position has been distorted by Santorum.

Casey said the Senate measure backed by moderate Republican senators Arlen Specter and John McCain is not perfect, but is better than nothing.

A new ad by Santorum running statewide repeatedly quotes Casey saying "I would vote yes" on the legislation and attacks the plan as an insult to taxpaying Americans.

Visitors to a new Web site showing the ad can click to order bumper stickers and yard signs that say Casey is "for amnesty" and "13 million illegal aliens are counting on him."

Hazleton Mayor Lou Barletta, who has gained national attention for promoting a local anti-illegal-immigration law considered to be one of the nation's toughest, has made recorded calls to voters on Santorum's behalf.

"Rick Santorum has been getting pretty desperate in the closing days of this campaign," Casey said. "He's trying to find something that will bring me down."

Politics, not demographics
Just how much the issue of illegal immigration resonates in Pennsylvania is unclear. While there are pockets of communities in Pennsylvania that have seen an influx in immigration, the state ranks 31st in the percent of foreign-born residents. Foreign-born residents make up only about 5 percent of the state's population, compared with 12 percent of the nation's population, according to the Migration Policy Institute.

"This is about politics. It's not about demographics," said Gordon Dejong, a professor of sociology and demography at Penn State University.

Polls have consistently shown that about 7 percent to 8 percent of Pennsylvania voters see immigration as the most important issue in the race, but among those voters, Santorum is perceived as favorable over Casey, said Terry Madonna, a pollster at Franklin and Marshall College. "It's not going to transform the election, but it's one issue that works in his favor," Madonna said.

Santorum's first TV ad discussed his father and grandfather's emigration from Italy to the U.S. and accused others of entering "with more sinister intentions."

Immigration vs. economy
The senator said Senate passage on Sept. 29 of a bill authorizing 700 new miles of fencing on the southern border provided an opportunity for him to stress the issue again.

Jonathon Lester, 20, a student at Grove City College from West Chester, who heard him speak on the issue during a recent stop at his university, said Santorum's views on immigration reinforced his support for him.

"He makes me proud to be a Pennsylvanian," Lester said.

But Rebecca Cooper, 32, a fourth-generation steel worker and union leader from Pittsburgh who joined a rally for Casey outside a Senate debate last week, said she doesn't think Pennsylvanians are focused on immigration.

"People who can't pay their gas bill, and their wages are getting cut, and their son is at war without the proper equipment. All that is much more immediate than a problem like immigration," Cooper said.

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